1. Field of the Invention
The present invention relates to an information processor, a method of updating a program and an information processing system and, more particularly, to an information processor, a program updating method and an information processing system suitable for updating a program such as a basic input/output system (BIOS) via a network.
2. Description of the Related Art
Networks of a kind represented by the Internet have been developed, to which network users can connect personal computers or the like to obtain various kinds of information.
A connection to the Internet or the like can be made through a communication network such as an analog telephone network or the Integrated Services Digital Network (ISDN). Recently, it has become possible to gain access to networks including the Internet through cables of a cable television (CATV) system.
For access to a network such as the Internet, an information processor having a transmitting and receiving circuit for transmission and reception through a predetermined communication network is used.
FIG. 9 shows an example of such an information processor using a modem 105 and capable of transmission and reception through an analog telephone circuit. A central processing unit (CPU) 101 executes various processings in accordance with programs stored in a flash electrically erasable programmable ROM (hereinafter referred to simply as "flash ROM") 102. Necessary data for execution of various processings performed by the CPU 101 and other data are suitably stored in a RAM 103. The CPU 101 receives data transmitted from the analog telephone circuit by using the modem 105. The CPU 101 processes the received data and displays, for example, received image data on a display unit (not shown) through a display interface 106.
A basic input/output system (BIOS), which is run by the CPU 101 when the processor is started up, and which is a basic program (a group of hardware-dependent control programs) for setting a configuration of the RAM 103 or initialization of a floppy disk drive 104, is stored in the flash ROM 102 as well as the programs for processing data supplied through the modem 105. The flash ROM 102 is an electrically erasable and programmable nonvolatile memory in which stored contents can be changed. The flash ROM 102 of such an erasable and programmable type is used to enable the BIOS to be updated according to a change in the specifications of units connected to the processor or according to updating of the operating system (OS) of the processor.
The BIOS in this information processor is updated as described below. First, a predetermined program for updating the BIOS is started and the BIOS stored in the flash ROM 102 is recorded on a floppy disk by the floppy disk drive 104. Thereafter, the floppy disk is taken out and another floppy disk on which a new BIOS is recorded is inserted into the floppy disk drive 104, and the new BIOS is stored in the flash ROM 102.
The step of recording the former BIOS on a floppy disk in this updating process is performed for the purpose of reinstalling the former BIOS if updating of the BIOS ends in failure, for example, if the floppy disk on which the new BIOS is recorded has such a defect that the new BIOS cannot be read out, or if the program of the new BIOS has a defect (bug) and cannot run normally.
However, BIOS updating is performed in a different manner in the case of an information processor having no floppy disk drive, e.g., a set top box (STB) used for access to a network such as the Internet through a cable of a CATV system. For example, in such an information processor, an external terminal unit is connected to a predetermined terminal provided in the information processor, and a BIOS is saved to the terminal unit before it is updated. For such BIOS updating, complicated operations are required.